CN111398869B - Mutual inductor handover test device and test method thereof - Google Patents
Mutual inductor handover test device and test method thereof Download PDFInfo
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- CN111398869B CN111398869B CN202010244602.7A CN202010244602A CN111398869B CN 111398869 B CN111398869 B CN 111398869B CN 202010244602 A CN202010244602 A CN 202010244602A CN 111398869 B CN111398869 B CN 111398869B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/02—General constructional details
- G01R1/04—Housings; Supporting members; Arrangements of terminals
- G01R1/0408—Test fixtures or contact fields; Connectors or connecting adaptors; Test clips; Test sockets
- G01R1/0416—Connectors, terminals
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/20—Modifications of basic electric elements for use in electric measuring instruments; Structural combinations of such elements with such instruments
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/025—Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/14—Circuits therefor, e.g. for generating test voltages, sensing circuits
Abstract
The invention discloses a mutual inductor handover test device and a test method thereof, and the mutual inductor handover test device comprises a test wire clamp, a switching device and a tester, wherein the test wire clamp is connected to the input end of the switching device through a test wire, a test port of the switching device is connected to the tester, the test wire clamp can clamp a screw on a secondary side terminal of a mutual inductor, the switching device is used for wiring and short-circuiting a secondary winding of the mutual inductor, and the tester comprises an insulation resistance tester, a transformation ratio tester, a mutual inductor characteristic tester and a direct current resistance tester. According to the invention, the test wire clamp and the switching device are connected through the test wire clamp, the switching device and different testers, the switching device is connected to the secondary winding of the mutual inductor at one time, various tests during mutual inductor connection are realized, and the functions of open circuit, short circuit and grounding operation of the secondary winding are quickly completed only through the switching of the switching device, so that the test time is shortened, and the test efficiency is improved.
Description
Technical Field
The invention relates to a mutual inductor transfer test device and a test method thereof, and belongs to the technical field of mutual inductor transfer test equipment.
Background
When we are testing the mutual inductor at present, the items of the test are as follows:
| insulation test | |
| 1. Primary to secondary insulation resistance | 4. |
| 2. Primary to secondary |
5. Excitation characteristic, polarity correction and secondary winding |
| 3. Insulation resistance of secondary winding with earth connection |
During the test, there are two problems:
in a first aspect: in the above test items, the positions of the test wires required to be accessed to the secondary terminals are different, the short circuit states of the outlet terminals of the secondary windings are different, and testers are required to frequently change the positions of the test wires accessed to the secondary terminals and the short circuit states of the secondary terminals to meet the requirements of various tests, which wastes time and labor. The specific problems are as follows:
(1) When the mutual inductor is subjected to primary-to-secondary insulation resistance and primary-to-secondary alternating current withstand voltage tests, the tests can be carried out only after the mutual inductor is subjected to primary short circuit and all outlet terminals of the secondary winding are subjected to short circuit grounding.
(2) When the mutual inductor is subjected to an insulation resistance test of grounding between secondary windings, the outlet terminal of the tested secondary winding of the mutual inductor needs to be in short circuit, and the outlet terminal of the non-tested secondary winding needs to be in short circuit and grounded, so that the grounding test among the secondary windings can be completed. The more secondary windings are, the more short circuit conversion times are, and the more test line conversion times are.
(3) When the transformer is subjected to the transformation ratio test, the outgoing line terminal of the tested secondary winding of the transformer needs to be opened and connected into the test line, and the outgoing line terminal of the non-tested secondary winding is in short circuit and grounded, so that the transformation ratio test of each secondary winding can be completed. The more secondary windings, the more times the short-circuit is switched. The more test line changes.
(4) When the excitation characteristic, the polarity correction and the direct current resistance test of the secondary winding are carried out on the mutual inductor, the outlet terminal of the tested secondary winding of the mutual inductor needs to be opened and connected with a test wire, and the outlet terminal of the non-tested secondary winding is opened, so that the test can be finished. The more secondary windings, the more test line changes.
Summarizing the problems:
in the above various tests, the requirements of the position of the test wire connected into the secondary terminal and the short circuit state of the secondary winding outgoing line terminal are as follows:
in order to solve the problem that the position of a test line and the short-circuit state of a secondary terminal need to be frequently changed during a mutual inductor test, a fast, convenient and reliable switching method and a device need to be developed to solve the problems.
In a second aspect: when carrying out experimental wiring and short circuit to mutual-inductor secondary terminal, reliable access test wire and short circuit mutual-inductor's secondary terminal also is a problem that takes time and labouring. There are several major problems:
(1) The test usually adopts the short circuit mode that stranded bare conductor twines secondary terminal. Because the bare conductor has certain elasticity, and the area of each secondary terminal nut is limited, and the nut surface is smooth, stranded bare conductor is easy to slip from the nut. When the mode of adopting the nut to screw up, need all nut pine take off, the reuse bare conductor twines, screws up the nut again, because the wire is softer, appears the crimping easily and not tightly leads to the bad contact condition, and wastes time and energy.
(2) Also adopt traditional experimental fastener to carry out the short circuit to the secondary terminal in the experiment, but because the area of terminal nut is limited, and the nut surface is smooth, traditional experimental fastener is also followed the nut easily and is located the slippage.
(3) In order to make the short circuit more firm, sometimes we adopt to remove all the secondary terminal bolts of the mutual inductor, insert the secondary terminal bolts into the secondary terminal holes by using test wire clamps and then clamp, although this method is more reliable than the above method, the time consumption is too long, and the removed nut gasket is easy to lose.
When above utilizing bare conductor and test fastener to the short circuit of secondary terminal, not only the operation is very inconvenient. The slippage back leaks the short circuit easily to appear, leads to experimental termination, influences test data, and the extension test time secondary side discharges when making withstand voltage test, leads to equipment to damage.
The above three problems are summarized: slipping, short circuit leakage, time and labor waste. Is the problem to be solved by the existing short-circuit method. In order to overcome the defects of the existing short-circuit method, it is necessary to develop a quick, convenient and reliable test wire clamp to solve the problems.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the utility model provides a mutual inductor handing-over test device and a test method thereof, which are used for solving the problems in the prior art.
The technical scheme adopted by the invention is as follows: the utility model provides a mutual-inductor handing-over test device, includes experimental fastener, auto-change over device and tester, and experimental fastener passes through the test wire to be connected to auto-change over device's input, and auto-change over device's test port is connected to the tester, and experimental fastener can press from both sides the screw of hitting mutual-inductor secondary side terminal, and auto-change over device is to mutual-inductor secondary winding's wiring and short circuit, and the tester includes insulation resistance tester, transformation ratio tester, mutual-inductor characteristic tester and direct current resistance tester.
Preferably, above-mentioned experimental fastener adopts the crocodile to press from both sides the structure, including two chucks of mutual swivelling joint and the reset spring who is located two chuck swivelling joint departments, two chuck front ends set up two arc interlock of symmetry and keep silent, two arc interlock keep silent can the centre gripping to the mutual-inductor on the screw all around and the gasket between the recess, two chuck tail ends are provided with the wiring socket.
Preferably, the middle parts of the front ends of the two chucks are provided with locking screws, the locking screws penetrate through one of the two chucks and are in screwed connection with the other chuck and movably penetrate through the other chuck, the locking screws penetrate through the two chucks (the through hole at the other chuck is a strip-shaped through hole, and the strip-shaped through hole is arranged along the length direction of the two chucks.
Preferably, each arc-shaped occlusion jaw is a thin sheet integrated with the chuck, and an arc-shaped groove is formed in the middle of the occlusion side of the thin sheet.
Preferably, each of the arcuate biting jaws tapers in thickness toward the biting side.
Preferably, the switching device includes four switching circuits, each of which is: the first group of secondary winding switching circuits, the second group of secondary winding switching circuits, the third group of secondary winding switching circuits and the fourth group of secondary winding switching circuits respectively comprise I + input ends, I-input ends, U + input ends, U-input ends, a first switching switch, a second switching switch, an output end E, an output end L and an output end D, the I + input ends and the U + input ends are connected to one end of the secondary winding of the mutual inductor in parallel, the I-input ends and the U-input ends are connected to the other end of the secondary winding of the mutual inductor in parallel, the I + input ends are respectively connected to the output end D and the I-input ends through the first switching switch, and the I-input ends are respectively connected to the output end E and the output end L through the second switching switch.
Preferably, the I + input end and the U + input end and the I-input end and the U-input end are respectively connected to two wiring jacks at the tail ends of the two test wire clamps.
Preferably, the switching device further comprises a junction box, a plurality of wire insertion holes are formed in the junction box, and the I + input end, the I-input end, the U + input end, the U-input end, the output end E, the output end L and the output end D are arranged on the junction box.
A test method of a mutual inductor handover test device comprises the following steps: before testing, I + input ends and U + input ends and I-input ends and U-input ends in a first group of secondary winding switching loops, a second group of secondary winding switching loops, a third group of secondary winding switching loops and a fourth group of secondary winding switching loops of a switching device are respectively connected with testing lines L1-L8, one testing line corresponds to the I + input ends and the U + input ends or the I-input ends and the U-input ends, and then the other ends of the testing lines L1-L8 are respectively connected with a port 1S1 and a port 1S2 of a secondary winding 1S of a mutual inductor through testing line clamps; 2S1 port and 2S2 port of 2S; 3S1 port and 3S2 port of 3S; the 4S1 port and the 4S2 port of the 4S are connected, and a secondary insulation resistance test, an insulation resistance test of grounding between secondary windings, a transformation ratio test, an excitation characteristic and polarity correction test and a direct current resistance test are carried out for the first time.
The method for testing the primary insulation resistance and the secondary insulation resistance comprises the following steps: the method comprises the steps that a P1 end and a P2 end of a primary winding (P) of a mutual inductor are in short circuit, four change-over switches in a first group of secondary winding change-over loops of a switching device, a second group of secondary winding change-over loops, a third group of secondary winding change-over loops and a fourth group of secondary winding change-over loops are all switched to an I-input end corresponding to each change-over switch, so that 1S1 port and 1S2 port of a secondary winding 1S of the mutual inductor, 2S1 port and 2S2 port of the secondary winding 2S, 3S1 port and 3S2 port of the secondary winding 3S and 4S1 port and 4S2 port of the secondary winding 4S are in short circuit, the first group of secondary winding change-over loops, the second group of secondary winding change-over loops, the third group of secondary winding change-over loops and four change-over switches in the fourth group of secondary winding change-over loops are switched to an output end E, the secondary windings 1S to 4S of the mutual inductor are all in a grounding state, an L end test wire of the insulation resistance tester is connected to the P1 end and the P2 end of the primary winding (P) of the mutual inductor, and an E end of the insulation resistance tester is grounded to test the primary resistance of the mutual inductor; when a primary-to-secondary alternating current withstand voltage test is carried out, a high-voltage output line of the alternating current withstand voltage test device is connected to a P1 end and a P2 end of a primary winding (P) of the mutual inductor, and the mutual inductor is subjected to a primary-to-secondary alternating current withstand voltage test;
the test method of the insulation resistance of the grounding between the secondary windings comprises the following steps: after a primary insulation resistance test and a secondary insulation resistance test are completed, keeping a state of a switching device during the primary insulation resistance test and the secondary insulation resistance test, switching two output ends L of a switch in a first group of secondary windings of the switching device, wherein at the moment, a port 1S1 and a port 1S2 of a secondary winding 1S of a mutual inductor are short-circuited to the output ends L, ports 2S1 and 2S2 of the secondary winding 2S of the mutual inductor, a port 3S1 and a port 3S2 of a secondary winding 3S and a port 4S1 and a port 4S2 of the secondary winding 4S of the mutual inductor are short-circuited and are in a grounding state, connecting a test wire of an insulation resistance tester to the output ends L and the output ends E, performing the grounding insulation resistance test between the secondary winding 1S and the secondary winding 2S, the secondary winding 3S and the secondary winding 4S of the mutual inductor, performing the grounding insulation resistance test between the secondary winding 2S and the secondary winding 4S of the secondary winding 1S, the secondary winding 3S and the secondary winding 4S, performing the grounding insulation resistance test between the secondary winding 1S and the secondary winding 2S, and the secondary winding 4S, and the same method when the secondary resistance test is performed;
the transformation ratio test method comprises the following steps: after completing the insulation resistance test of the secondary winding 1S to the secondary winding 2S, the secondary winding 3S and the secondary winding 4S, keeping the state of a switching device when the insulation resistance test of the secondary winding 1S to the secondary winding 2S, the secondary winding 3S and the secondary winding 4S to the ground is performed, switching a first switch in a first group of switching loops of the switching device to an output end D, wherein at the moment, an open circuit is formed between a port 1S1 and a port 1S2 of the secondary winding 1S of the transformer, ports 2S1 and 2S2 of the secondary winding 2S of the transformer, ports 3S1 and 3S2 of the secondary winding 3S and ports 4S1 and 4S2 of the secondary winding 4S of the transformer are all short-circuited and are in a grounding state, connecting a high-voltage side testing wire of a transformation ratio tester to a port P1 and a port P2 of the primary winding (P) of the transformer, connecting a low-voltage side testing wire of the transformation ratio tester to an output end L and an output end D of the switching device, performing the transformation ratio test of the primary winding P and the secondary winding 1S of the secondary winding 1S, and the secondary winding 2S2 when the secondary winding is the primary winding and the secondary winding 4S, and the secondary winding 4S1, and the secondary winding 1 when the secondary winding are in the transformation ratio test;
the method for calibrating the excitation characteristic and the polarity comprises the following steps: after the transformation ratio test of the primary winding P and the secondary winding 1S is completed, the three change-over switches in the second group of secondary winding change-over circuits, the third group of secondary winding change-over circuits and the fourth group of secondary winding change-over circuits of the change-over switches are all switched to a disconnection state under the state of the change-over switches in the transformation ratio test of the primary winding P and the secondary winding 1S, the grounding on the output end E is disconnected, and at the moment, an open circuit is formed between the port 1S1 and the port 1S2 of the secondary winding 1S of the mutual inductor; the opening between the 2S1 port and the 2S2 port of the secondary winding 2S of the mutual inductor, the opening between the 3S1 port and the 3S2 port of the 3S, and the opening between the 4S1 port and the 4S2 port of the 4S are both in an ungrounded state, a test wire of a mutual inductor characteristic tester is connected to an output end L and an output end D on a switching device, the excitation characteristic test of a primary winding P and the secondary winding 1S is carried out on the mutual inductor, and when the excitation characteristic test of the primary winding P and the secondary winding 2S, the primary winding P and the secondary winding 3S, and the excitation characteristic test of the primary winding P and the secondary winding 4S are carried out, the switching method is the same as that when the excitation characteristic test of the secondary winding 1S is carried out;
when the polarity correction test is carried out, a high-voltage side test wire of the mutual inductor characteristic tester is connected to a P1 end and a P2 end of a primary winding (P) of the mutual inductor, a low-voltage side test wire of the mutual inductor characteristic tester is connected to an output end L and an output end D, the polarity correction test of the primary winding P and a secondary winding 1S is carried out on the mutual inductor, and when the polarity correction test of the primary winding P and the secondary winding 2S, the primary winding P and the secondary winding 3S and the polarity correction test of the primary winding P and the secondary winding 4S are carried out, the polarity correction test is the same as that of the secondary winding 1S;
the direct current resistance test method comprises the following steps: after the excitation characteristic and polarity correction tests of the primary winding P and the secondary winding 1S are completed, the state of the switching device during the excitation characteristic and polarity correction tests is kept, and at the moment, an open circuit is formed between the port 1S1 and the port 1S2 of the secondary winding 1S of the mutual inductor; the ports 2S1 and 2S2 of the secondary winding 2S of the mutual inductor, the ports 3S1 and 3S2 of the secondary winding 3S and the ports 4S1 and 4S2 of the secondary winding 4S are all open-circuited and are in an ungrounded state, a test wire of a direct current resistance tester is connected to an output end L and an output end D on a switching device, the direct current resistance test of the secondary winding 1S is carried out on the mutual inductor, and when the direct current resistance test of the secondary winding 2S, the secondary winding 3S and the secondary winding 4S is carried out, the switching method is the same as the direct current resistance test of the secondary winding 1S.
The invention has the beneficial effects that: compared with the prior art, the invention has the following effects:
(1) According to the invention, the test wire clamp is connected with the switching device through the test wire clamp, the switching device and different testers, the switching device is connected to the secondary winding of the mutual inductor at one time, the insulation resistance test, the transformation ratio test, the mutual inductor characteristic test and the direct current resistance test during mutual inductor connection are realized through switching the position of the switching device and connecting different testers, when various tests of the mutual inductor are completed, the functions of open circuit, short circuit and grounding operation of the secondary side winding can be rapidly completed only through switching of the switching device, the test time is shortened, and the test efficiency is improved; the current transformer can be applied to current transformers of various voltage grades, and can also be applied to voltage transformers of various voltage grades;
(2) The arc-shaped occluding jaw utilizes the groove as a fixed point of the test wire clamp, and the original test wire clamp can only be clamped outside the screw and cannot be clamped in the groove between the screw and the gasket;
(3) Because the test wire clamp is clamped by the counterforce of the spring, a locking screw is added between the middle parts of the front ends of two chucks (an upper chuck and a lower chuck) of the test wire clamp for locking, and the locking screw can ensure that the circular arc jaw at the front end of the test wire clamp can not slip off from the screw due to external force after the test wire clamp is clamped on the clamping screw, and the test wire clamp is convenient to design and operate and can be screwed in by a single hand. After the circular arc-shaped jaw at the front end of the test wire clamp is occluded with the screw groove, the screw is screwed in and fixed, so that the upper chuck and the lower chuck of the test wire clamp are relatively fixed, the situation that the jaw of the test wire clamp is opened by the counteracting elastic force of the spring due to the action of external force is prevented, the test wire clamp is easy to slip off and fall off is avoided, and the problem that the screw cannot be screwed in due to interference between the upper chuck and the lower chuck and the screw due to over-positioning is solved by adopting the strip-shaped through hole at the position where one chuck penetrates into the locking screw;
(4) The arc-shaped occlusion jaw with the sheet structure is convenient to adapt to screws connected with secondary windings on mutual inductors with different sizes, and the gradually-thinned structure is adopted, so that the test wire clamp is conveniently clamped in the irregular groove to the maximum extent, the clamping is stable and reliable, and the electric conduction is more reliable;
(5) The four groups of switching loops are adopted, so that a mutual inductor with the secondary windings not more than 4 groups can be tested, the switching loops are simple and convenient to switch, and the first switching switch and the second switching switch can realize the adjustment of three positions (disconnection and connection to two output ends);
(6) The mode that the I + input end and the U + input end share one test wire clamp with the I-input end and the U-input end is adopted, so that the equipment is simplified, the operation is easy, the connection is reliable, the probability of short circuit of terminals between secondary windings is reduced, and the test safety is improved;
(7) The switching device is simple in structure, convenient and fast to plug in the test wire and reasonable in layout, plug-in of the corresponding socket is achieved conveniently and fast, plug-in errors are avoided, and wiring and short connection of the secondary winding of the mutual inductor are completed fast through switching of the switching device. The test time is shortened, and the test efficiency is improved; the panel of the switching device is provided with an identification reticle (switching loop diagram) of a switching loop, so that staff can conveniently master wiring requirements under various test items at any time, the teaching of the staff is facilitated, the test of the test items is standardized, and the accuracy of test data is ensured;
(8) According to the test method, the shared part between the previous time and the next time can be utilized, the connection of the conducting wire and the switching of the change-over switch are reduced, so that the test efficiency is greatly improved, the test time is shortened, and the problems that the test wire is easy to slip when being connected into the test wire and the short-circuit wire, the position of the test wire needs to be frequently changed and the short-circuit state of the secondary terminal needs to be effectively solved, so that the aim of reliable and quick test is fulfilled.
Drawings
FIG. 1 is a schematic view of the connection structure of the present invention;
FIG. 2 is a schematic view of a locking connection of the test clamp;
FIG. 3 is a schematic view of the structure of a test clip;
FIG. 4 is a schematic diagram of a groove structure at a clamping screw of the test clamp;
FIG. 5 is a schematic diagram of a switching loop;
FIG. 6 is a schematic diagram of a primary to secondary insulation resistance test switching circuit;
FIG. 7 is a schematic diagram of an insulation resistance test switching circuit between secondary windings and ground;
FIG. 8 is a schematic diagram of a ratio-change trial switching circuit;
FIG. 9 is a schematic diagram of a switching circuit for excitation characteristic and polarity calibration tests;
FIG. 10 is a schematic diagram of a DC resistance test switching circuit;
FIG. 11 is a perspective view of the switching device;
fig. 12 is a schematic top view of the switching device.
Detailed Description
The invention is further described with reference to the accompanying drawings and specific embodiments.
Example 1: as shown in fig. 1 to 12, a mutual inductor handover test device comprises a test wire clamp 1, a switching device 2 and a tester 3, wherein the test wire clamp 1 is connected to an input end of the switching device 2 through a test wire, a test port of the switching device 2 is connected to the tester 3, the test wire clamp 1 can clamp a screw of a secondary side terminal of a mutual inductor, the switching device 2 is used for connecting and short-circuiting a secondary winding of the mutual inductor, and the tester 3 comprises an insulation resistance tester, a transformation ratio tester, a mutual inductor characteristic tester and a direct current resistance tester.
Preferably, the test wire clamp 1 adopts an alligator clamp structure, and includes two chucks 101 rotatably connected to each other and a return spring located at the rotational connection position of the two chucks 101, two symmetrical arc-shaped engagement jaws 104 are provided at the front ends of the two chucks 101, the two arc-shaped engagement jaws 104 can clamp the periphery of a screw on a transformer and a groove between gaskets, as shown in fig. 4, a wiring socket 105 is provided at the tail end of the two chucks 101.
Preferably, a locking screw 102 is installed at the middle of the front ends of the two clamping heads 101, the locking screw 102 penetrates through the two clamping heads 101 and is screwed with one of the two clamping heads 101 and movably penetrates through the other of the two clamping heads 101, a through hole through which the locking screw 102 penetrates through the other of the two clamping heads 101 is a strip-shaped through hole 103, and the strip-shaped through hole 103 is arranged along the length direction of the two clamping heads 101.
Preferably, each of the arcuate engaging jaws 104 is a thin sheet integrated with the chuck, and an arcuate groove is formed in the middle of the sheet near the engaging side.
Preferably, each arcuate biting jaw 104 tapers in thickness toward the biting side.
Preferably, the switching device 2 includes four switching circuits, each of which is: the first group of secondary winding switching circuits, the second group of secondary winding switching circuits, the third group of secondary winding switching circuits and the fourth group of secondary winding switching circuits respectively comprise I + input ends, I-input ends, U + input ends, U-input ends, a first switching switch, a second switching switch, an output end E, an output end L and an output end D, the I + input ends and the U + input ends are connected to one end of the secondary winding of the mutual inductor in parallel, the I-input ends and the U-input ends are connected to the other end of the secondary winding of the mutual inductor in parallel, the I + input ends are respectively connected to the output end D and the I-input ends through the first switching switch, and the I-input ends are respectively connected to the output end E and the output end L through the second switching switch.
The first group of secondary winding switching loops consists of switching switches S1 and S5, test line output sockets (I +, U +; U-, U +) and corresponding connecting lines.
The second group of secondary winding switching loop consists of switching switches S2 and S6, test line output sockets (I +, U-, U +) and corresponding connecting lines.
The third group of secondary winding switching loop consists of switching switches S3 and S7, a test wire output socket (I +, U +; U-, U +) and a corresponding connecting wire;
the fourth group of secondary winding switching loops consists of switching switches S4 and S8, test line output sockets (I +, U +; U-, U +) and corresponding connecting lines;
preferably, the I + input end and the U + input end and the I-input end and the U-input end are respectively connected to two wiring jacks at the tail ends of the two test wire clamps.
Preferably, the switching device 2 further includes a junction box 201, the junction box 201 is provided with a plurality of wire insertion holes 202 for an I + input end, an I-input end, a U + input end, a U-input end, an output end E, an output end L and an output end D, the wire insertion holes 202 for the I + input end, the I-input end, the U + input end and the U-input end of each secondary winding terminal are located at the rear side of the upper end face of the junction box 201, the wire insertion holes 202 for the output end E, the output end L and the output end D are located at the right lower side of the upper end face of the junction box 201, a switching knob 203 for connecting a first switching switch and a second switching switch of each secondary winding terminal is arranged at the upper end face of the junction box 201 near the longitudinal middle portion, and an identification marking line 204 for switching a loop is arranged at a position of the upper surface of the junction box 201 corresponding to the wire insertion holes 202 and the switching knobs 203.
Example 2: a test method of a mutual inductor handover test device comprises the following steps: according to the test sequence of the mutual inductor test items, firstly carrying out an insulation test and then carrying out a characteristic test. The following is a description of switching during testing by the switching device according to this test procedure: before testing, firstly, testing lines L1-L8 and testing line output sockets I + and U + in the first, second, third and fourth groups of secondary winding switching loops of the switching device are tested; u + and U + are respectively connected, and then the other ends of the test lines L1-L8 are respectively connected with 1S1 and 1S2 of a secondary winding 1S of the mutual inductor; 2S1, 2S2 of 2S; 3S1, 3S2 of 3S; 4S1 and 4S2 of the 4S are connected, the E end of the test port is grounded, and a primary insulation resistance test, a secondary insulation resistance test, a grounded insulation resistance test between secondary windings, a transformation ratio test, an excitation characteristic and polarity correction test and a direct current resistance test are performed.
The primary insulation resistance test method to the secondary insulation resistance test method comprises the following steps: when a secondary insulation resistance test is carried out, the ends P1 and P2 of the primary winding (P) of the mutual inductor are in short circuit, and the change-over switches S1-S4 in the first, second, third and fourth groups of secondary winding switching loops of the switching device are switched to the positions in the graph 6, wherein at the moment, 1S1 and 1S2 of the secondary winding 1S of the mutual inductor are respectively connected with the first, second, third and fourth groups of secondary winding switching loops; 2S1 and 2S2 of 2S; 3S1 and 3S2 of 3S; 4S1 and 4S2 of the 4S are all in short circuit, and the change-over switches S5-S8 in the first, second, third and fourth groups of secondary winding switching loops of the switching device are switched to the positions in the figure 6, so that the secondary windings 1S-4S of the mutual inductor can be in the grounding state. And connecting an L-end test wire of the insulation resistance tester to the short-circuit ends of P1 and P2 of the primary winding (P) of the transformer, grounding the E end of the insulation resistance tester, and carrying out a primary insulation resistance test on the transformer. When a primary-to-secondary alternating current withstand voltage test is carried out, a high-voltage output line of the alternating current withstand voltage test device is connected to the short-circuit ends P1 and P2 of a primary winding (P) of the mutual inductor, and the primary-to-secondary alternating current withstand voltage test is carried out on the mutual inductor;
the method for testing the insulation resistance of the secondary winding which is grounded comprises the following steps: after the primary-to-secondary insulation resistance test is completed, the insulation resistance test between the secondary windings and the ground can be performed, and the insulation resistance test between the secondary windings 2S, 3S and 4S and the insulation resistance test between the secondary windings 1S and the ground are taken as an example to explain, in the state of the switching device maintained in the primary-to-secondary insulation resistance test, the switches S1 and S5 in the switching circuit of the first group of secondary windings of the switching device are switched to the positions in fig. 7 (actually, only the position of S5 needs to be switched), and the switches S2 to S4 and S6 to S8 in the switching circuits of the second group of secondary windings of the switching device are switched to the positions in fig. 7 (actually, the state of the primary-to-secondary insulation resistance test is maintained, switching is not needed), so that the switches 1S1 and 1S2 of the secondary winding 1S of the transformer are short-circuited but not grounded; 2S1 and 2S2 of a secondary winding 2S of the mutual inductor; 3S1 and 3S2 of 3S; 4S is in short circuit between 4S1 and 4S2 and is in a grounding state. Test lines of the insulation resistance tester are connected to the test ports L and E. At this time, the insulation resistance test of the secondary winding 1S, the secondary windings 2S, 3S and 4S and the ground can be carried out on the mutual inductor. When the other secondary windings 2S, 3S and 4S are tested, the switching principle is the same;
the transformation ratio test method comprises the following steps: after the insulation resistance test of the secondary winding 1S to the secondary windings 2S, 3S, 4S and to the ground is completed, the transformation ratio test can be performed, and the transformation ratio test of the primary winding P and the secondary winding 1S will be described as an example: in the state of the switching device maintained during the insulation resistance test of the secondary winding 1S to the secondary windings 2S, 3S and 4S and the ground, the switches S1 and S5 in the switching circuit of the first group of secondary windings of the switching device are switched to the positions in fig. 8 (actually, only the position of S1 needs to be switched), and the switches S2 to S4 and S6 to S8 in the switching circuits of the second group of secondary windings of the switching device are switched to the positions in fig. 8 (actually, the state of the secondary winding 1S to the secondary windings 2S, 3S and 4S and the ground during the insulation resistance test is maintained without switching), at this time, the circuit is opened between the switches 1S1 and 1S2 of the secondary winding 1S of the transformer; 2S1 and 2S2 of a secondary winding 2S of the mutual inductor; 3S1 and 3S2 of 3S; 4S1 and 4S2 of 4S are both shorted and in a grounding state. And connecting a high-voltage side test wire of the transformation ratio tester to the ends P1 and P2 of the primary winding (P) of the transformer. The low side test line of the ratio tester is connected to the test ports L and D on the switching device. Then, the transformer can be subjected to a transformation ratio test of the primary winding P and the secondary winding 1S. When the transformation ratio of the other secondary windings 2S, 3S and 4S is tested, the switching principle is the same;
the method for calibrating the excitation characteristic and the polarity comprises the following steps: after the transformation ratio test of the primary winding P and the secondary winding 1S is completed, the excitation characteristic and polarity calibration test can be performed, and the excitation characteristic and polarity calibration test of the primary winding P and the secondary winding 1S is described as an example: in the state of the switching device maintained during the transformation ratio test of the primary winding P and the secondary winding 1S, the switches S1 and S5 in the switching device first group secondary winding switching loop are switched to the positions in the figure 9 (actually, the state of the primary winding P and the secondary winding 1S during the transformation ratio test is maintained, and switching is not needed), the switches S2-S4 in the switching device second group secondary winding switching loop, the third group secondary winding switching loop and the fourth group secondary winding switching loop are switched to the positions in the figure 9, the grounding on the end E of the test port is disconnected, and at the moment, the circuit is opened between the 1S1 and the 1S2 of the transformer secondary winding 1S; 2S1 and 2S2 of a secondary winding 2S of the mutual inductor; 3S1 and 3S2 of 3S; 4S and 4S2 are both open and in an ungrounded state. And connecting the test wires of the transformer characteristic tester to the test ports L and D on the switching device. At this time, the excitation characteristics of the primary winding P and the secondary winding 1S of the transformer can be tested. The switching principle is the same for the excitation characteristic tests of the other secondary windings 2S, 3S, 4S.
When a polarity correction test is carried out, a high-voltage side test wire of the transformer characteristic tester is connected to the ends P1 and P2 of the primary winding (P) of the transformer. And connecting a low-voltage side test line of the transformer characteristic tester to the test ports L and D. The polarity correction test of the primary winding P and the secondary winding 1S can be carried out on the mutual inductor. When the polarity of the other secondary windings 2S, 3S and 4S is proofread and tested, the switching principle is the same;
the direct current resistance test method comprises the following steps: after the excitation characteristic and polarity correction test of the primary winding P and the secondary winding 1S is completed, a direct current resistance test can be performed, and the direct current resistance test of the secondary winding 1S is taken as an example for explanation, wherein in the state of the switching device maintained during the excitation characteristic and polarity correction test, the switching switches S1 and S5 in the first group of secondary winding switching loops of the switching device are switched to the positions in fig. 10 (the state during the excitation characteristic and polarity correction test is maintained actually, and switching is not needed), the switching switches S2 to S4 in the second, third and fourth groups of secondary winding switching loops of the switching device are switched to the positions in fig. 10 (the state during the excitation characteristic and polarity correction test is maintained actually, and switching is not needed), the grounding on the end E of the test port is released (the state during the excitation characteristic and polarity correction test is maintained actually, switching is not needed), and at this time, the 1S1 and 1S2 of the secondary winding 1S of the transformer are opened; 2S1 and 2S2 of a secondary winding 2S of the mutual inductor; 3S1 and 3S2 of 3S; 4S and 4S2 are both open and in an ungrounded state. The test lines of the dc resistance tester are connected to the test ports L and D on the switching device. At this time, the direct current resistance test of the secondary winding 1S can be performed on the transformer. When the direct current resistance tests of the other secondary windings 2S, 3S and 4S are carried out, the switching principle is the same.
The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and therefore the scope of the present invention shall be subject to the protection scope of the claims.
Claims (7)
1. The utility model provides a mutual-inductor handing-over test device which characterized in that: the testing device comprises a testing wire clamp (1), a switching device (2) and a tester (3), wherein the testing wire clamp (1) is connected to the input end of the switching device (2) through a testing wire, a testing port of the switching device (2) is connected to the tester (3), the testing wire clamp (1) can clamp and hit a screw of a secondary side terminal of a mutual inductor, the switching device (2) is used for wiring and short-circuiting a secondary winding of the mutual inductor, and the tester (3) comprises an insulation resistance tester, a transformation ratio tester, a mutual inductor characteristic tester and a direct current resistance tester; the switching device (2) comprises four groups of switching loops, which are respectively: the first group of secondary winding switching circuits, the second group of secondary winding switching circuits, the third group of secondary winding switching circuits and the fourth group of secondary winding switching circuits respectively comprise I + input ends, I-input ends, U + input ends, U-input ends, a first switching switch, a second switching switch, an output end E, an output end L and an output end D, wherein the I + input ends and the U + input ends are connected to one end of the secondary winding of the mutual inductor in parallel, the I-input ends and the U-input ends are connected to the other end of the secondary winding of the mutual inductor in parallel, the I + input ends are respectively connected to the output end D and the I-input ends through one switching switch, and the I-input ends are respectively connected to the output end E and the output end L through two switching switches; the test method of the mutual inductor transfer test device comprises the following steps: before testing, I + input ends and U + input ends and I-input ends and U-input ends in test lines L1-L8 and a first group of secondary winding switching loops, a second group of secondary winding switching loops, a third group of secondary winding switching loops and a fourth group of secondary winding switching loops of a switching device are respectively connected, one test line corresponds to the I + input ends and the U + input ends or the I-input ends and the U-input ends, the other ends of the test lines L1-L8 are respectively connected with a port 1S1 and a port 1S2 of a secondary winding 1S, a port 2S1 and a port 2S2 of a secondary winding 1S, a port 3S1 and a port 3S2 of a secondary winding 3S and a port 4S1 and a port 4S2 of a secondary winding 4S through test wire clamps, and after connection, a secondary insulation resistance test, an insulation resistance test of grounding between the secondary windings, a transformation ratio test, an excitation characteristic and polarity correction test and a direct current resistance test are carried out;
the method for testing the secondary insulation resistance in the primary insulation resistance test comprises the following steps: the method comprises the steps of short-circuiting the P1 end and the P2 end of a primary winding of a transformer, switching four change-over switches in a first group of secondary winding switch-over loops of a switching device, a second group of secondary winding switch-over loops, a third group of secondary winding switch-over loops and a fourth group of secondary winding switch-over loops to an I-input end corresponding to each change-over switch, enabling 1S1 port and 1S2 port of a secondary winding 1S of the transformer, 2S1 port and 2S2 port of the transformer, 3S1 port and 3S2 port of the transformer, and 4S1 port and 4S2 port of the transformer to be short-circuited, switching four change-over switches in a first group of secondary winding switch-over loops, a second group of secondary winding switch-over loops, a third group of secondary winding switch-over loops and a fourth group of secondary winding switch-over loops to an output end E, enabling the secondary windings 1S-4S of the transformer to be in a grounding state, connecting an L end wire of an insulation resistance tester to the P1 end and the P2 end of the primary winding of the transformer, grounding an E end of the insulation resistance tester, and testing the transformer to carry out primary resistance testing on the secondary resistance of the transformer; when a primary-to-secondary alternating current withstand voltage test is carried out, a high-voltage output line of the alternating current withstand voltage test device is connected to a P1 end and a P2 end of a primary winding of the mutual inductor, and the mutual inductor is subjected to a primary-to-secondary alternating current withstand voltage test;
the test method of the insulation resistance of the grounding between the secondary windings comprises the following steps: after a primary insulation resistance test and a secondary insulation resistance test are completed, keeping a state of a switching device during the primary insulation resistance test and the secondary insulation resistance test, switching two output ends L of a switch in a first group of secondary windings of the switching device, wherein at the moment, a port 1S1 and a port 1S2 of a secondary winding 1S of a mutual inductor are short-circuited to the output ends L, ports 2S1 and 2S2 of the secondary winding 2S of the mutual inductor, a port 3S1 and a port 3S2 of a secondary winding 3S and a port 4S1 and a port 4S2 of the secondary winding 4S of the mutual inductor are short-circuited and are in a grounding state, connecting a test wire of an insulation resistance tester to the output ends L and the output ends E, performing the grounding insulation resistance test between the secondary winding 1S and the secondary winding 2S, the secondary winding 3S and the secondary winding 4S of the mutual inductor, performing the grounding insulation resistance test between the secondary winding 2S and the secondary winding 4S of the secondary winding 1S, the secondary winding 2S and the secondary winding 4S, and performing the same insulation resistance test between the secondary winding 1S, the secondary winding 3S and the secondary winding 4S, and the secondary winding 1S, and the same method when the secondary resistance test is performed;
the transformation ratio test method comprises the following steps: after completing the insulation resistance test of the secondary winding 1S to the secondary winding 2S, the secondary winding 3S and the secondary winding 4S, keeping the state of a switching device when the insulation resistance test of the secondary winding 1S to the secondary winding 2S, the secondary winding 3S and the secondary winding 4S to the ground is performed, switching a first switch in a first group of switching loops of the switching device to an output end D, wherein at the moment, an open circuit is formed between a port 1S1 and a port 1S2 of the secondary winding 1S of the transformer, ports 2S1 and 2S2 of the secondary winding 2S of the transformer, ports 3S1 and 3S2 of the secondary winding 2S of the transformer and ports 4S1 and 4S2 of the secondary winding 4S are all short-circuited and in the ground state, connecting a high-voltage side test wire of a transformation ratio tester to a port P1 and a port P2 of the primary winding of the transformer, connecting a low-voltage side test wire of the transformation ratio tester to an output end L and an output end D of the switching device, performing the transformation ratio test of the primary winding P and the secondary winding 1S of the secondary winding 1S, and the primary winding P2S and the secondary winding 4S, and the secondary winding when the transformation ratio test of the secondary winding is the same as the primary winding 1 and the secondary winding 4S1, and the secondary winding 4S2, and the secondary winding when the secondary winding are subjected to the transformation ratio test method;
the method for calibrating the excitation characteristic and the polarity comprises the following steps: after the transformation ratio test of the primary winding P and the secondary winding 1S is completed, the three change-over switches in the second group of secondary winding change-over circuits, the third group of secondary winding change-over circuits and the fourth group of secondary winding change-over circuits of the change-over switches are all switched to a disconnection state under the state of the change-over switches in the transformation ratio test of the primary winding P and the secondary winding 1S, the grounding on the output end E is disconnected, and at the moment, an open circuit is formed between the port 1S1 and the port 1S2 of the secondary winding 1S of the mutual inductor; the opening between the 2S1 port and the 2S2 port of the secondary winding 2S of the mutual inductor, the opening between the 3S1 port and the 3S2 port of the 3S, and the opening between the 4S1 port and the 4S2 port of the 4S are both in an ungrounded state, a test wire of a mutual inductor characteristic tester is connected to an output end L and an output end D on a switching device, the excitation characteristic test of a primary winding P and the secondary winding 1S is carried out on the mutual inductor, and when the excitation characteristic test of the primary winding P and the secondary winding 2S, the primary winding P and the secondary winding 3S, and the excitation characteristic test of the primary winding P and the secondary winding 4S are carried out, the switching method is the same as that when the excitation characteristic test of the secondary winding 1S is carried out;
when the polarity correction test is carried out, a high-voltage side test wire of the mutual inductor characteristic tester is connected to a P1 end and a P2 end of a primary winding of the mutual inductor, a low-voltage side test wire of the mutual inductor characteristic tester is connected to an output end L and an output end D, the polarity correction test of the primary winding P and a secondary winding 1S is carried out on the mutual inductor, and when the polarity correction test of the primary winding P and the secondary winding 2S, the primary winding P and the secondary winding 3S and the polarity correction test of the primary winding P and the secondary winding 4S are carried out, the polarity correction test is the same as that of the secondary winding 1S;
the direct current resistance test method comprises the following steps: after the excitation characteristic and polarity correction tests of the primary winding P and the secondary winding 1S are completed, the state of the switching device during the excitation characteristic and polarity correction tests is kept, and at the moment, an open circuit is formed between the port 1S1 and the port 1S2 of the secondary winding 1S of the mutual inductor; the ports 2S1 and 2S2 of the secondary winding 2S of the mutual inductor, the ports 3S1 and 3S2 of the secondary winding 3S and the ports 4S1 and 4S2 of the secondary winding 4S are all open-circuited and are in an ungrounded state, a test wire of a direct current resistance tester is connected to an output end L and an output end D on a switching device, the direct current resistance test of the secondary winding 1S is carried out on the mutual inductor, and when the direct current resistance test of the secondary winding 2S, the secondary winding 3S and the secondary winding 4S is carried out, the switching method is the same as the direct current resistance test of the secondary winding 1S.
2. The instrument transformer handover test device according to claim 1, wherein: the test wire clamp (1) adopts an alligator clamp structure, and comprises two chucks (101) which are in mutual rotary connection and a reset spring positioned at the rotary connection position of the two chucks (101), wherein the front ends of the two chucks (101) are provided with two symmetrical arc-shaped occlusion jaws (104), the two arc-shaped occlusion jaws (104) can clamp the periphery of a screw on a mutual inductor and a groove between gaskets, and the tail ends of the two chucks (101) are provided with wiring sockets (105).
3. The instrument transformer handover test device according to claim 2, wherein: the middle parts of the front ends of the two chucks (101) are provided with locking screws (102), the locking screws (102) penetrate through the two chucks (101) and are in threaded connection with one of the two chucks (101) and movably penetrate through the other of the two chucks (101), the through holes at which the locking screws (102) penetrate through the other of the two chucks (101) are strip-shaped through holes (103), and the strip-shaped through holes (103) are arranged along the length direction of the two chucks (101).
4. The instrument transformer handover test device according to claim 2, wherein: each arc-shaped occlusion jaw (104) is a thin sheet integrated with the chuck, and an arc-shaped groove is arranged in the middle of one side, close to the occlusion, of the thin sheet.
5. The instrument transformer handover test device according to claim 2, wherein: each arcuate bite jaw (104) tapers in thickness toward the bite side.
6. The instrument transformer handover test device according to claim 1, wherein: the I + input end and the U + input end and the I-input end and the U-input end are respectively connected to two wiring jacks at the tail ends of the two test wire clamps.
7. The instrument transformer handover test device according to claim 6, wherein: the direct current transformer is characterized by further comprising a junction box (201), wherein an I + input end, an I-input end, a U + input end, a U-input end, an output end E, a plurality of wire inserting holes (202) of an output end L and an output end D are arranged on the junction box (201), the I + input end of each secondary winding terminal is connected, the I-input end, the wire inserting holes (202) of the U + input end and the U-input end are located on the rear side of the upper end face of the junction box (201), the wire inserting holes (202) of the output end E, the output end L and the output end D are located on the right lower side of the upper end face of the junction box (201), a first switching knob (203) and a second switching knob (203) which are connected with each secondary winding terminal are arranged on the upper end face of the junction box (201) and close to the longitudinal middle part, and an identification scribing line (204) of a switching loop is arranged on the upper surface of the junction box (201) corresponding to the wire inserting holes (202) and the switching knob (203).
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| CN105974348B (en) * | 2016-04-29 | 2018-08-10 | 国网山东省电力公司电力科学研究院 | Low-voltage current mutual inductor comprehensive detection system and its method |
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